1. Field of the Invention
The present invention relates generally to apparatus for the sharpening of tools, and, more particularly, to the sharpening of spatulas and the like flat bladed implements.
2. Description of the Prior Art
Many different devices have been developed for the sharpening of tools, and are commonplace in machine shops and the like. However, such devices, designed for precision sharpening of tools, are typically complex or require a high degree of skill in their operation. Other, simpler approaches also have been developed for day-to-day use in, for example, kitchens for the sharpening of culinary utensils. While such devices are generally simple in construction and operation, the quality of the sharpening process is typically quite low.
Problems are encountered in, for example, commercial restaurants and, most particularly, fast food restaurants involving the need to quickly and efficiently sharpen spatulas in a simple and convenient manner. In such establishments, food is cooked on a large metal surface and the cook utilizes the spatula for various purposes. Typically, the spatulas have a flat section, for turning the food during the cooking process, and a handle section at a relatively oblique angle with respect thereto. In order to turn the food on the cooking surface, it is beneficial that the leading edge of the spatula be relatively sharp in order to part the food from the grill. Once the cooking process has been completed, the cook then rotates the spatula to a reverse orientation from that for turning the food and employs the same as a scraper to clean particles of food from the grill. Again, it is highly beneficial that the end or leading edge of the spatula be kept relatively sharp for greatest efficiency.
The problem encountered in these environments is the dulling of the leading edge of the spatula during extended use, and thus the requirement for periodic sharpening of the tool. Currently, no fully convenient apparatus is available to aid in this task and the sharpening typically must be accomplished by hand so that the edge of the blade becomes non-straight or out-of-line. At the same time, it is necessary to provide a device which may be used by operators with a minimum of familiarity with machinery or machine tools but which device nonetheless provides accurate and fully satisfactory sharpening results even at the hands of inexperienced users.
Illustrative of one approach to these ends is U.S. Pat. No. 700,562 which provides a grooved or V-shaped sharpening member secured in reciprocable engagement with a knife blade. The sharpening member is caused to reciprocate in constant contact with the knife edge to effect sharpening thereof. While this device is satisfactory for sharpening a knife blade, it is ineffective for filing the edge of spatulas in view of the constant contact of the sharpening member with the tool.
Another device exemplary of those heretofore employed for sharpening tools is disclosed in U.S. Pat. No. 2,707,409. This device is designed for the sharpening of chainsaw blades, particularly by those unskilled in this area. Basically, there are provided means for locating the tooth to be sharpened and a guide to direct a file at an appropriate angle with respect thereto. Again, however, such apparatus is not totally satisfactory in the absence of any mechanism to prevent the file from engaging the chain on the return stroke.
Various fixtures or jigs have been developed to aid in the sharpening of tools. See, for example, U.S. Pat. Nos. 951,961 and 3,0ll,366. The common feature of such fixtures is the ability to adjust the device whereby the tool held in the fixture may be sharpened or abraded to a predetermined level whereupon further removal of metal is prevented. While satisfactory to this end, devices of this general type again fail to release the file from the tool on the reverse stroke and, by virtue of their guide rollers, cause the file to rapidly become dull.
Accordingly, the need exists to provide a tool sharpening apparatus which overcomes the manifest disadvantages of prior art apparatus, particularly for the sharpening of spatulas.